This invention relates to a remote control device and more particularly to an audio system for cars.
In conventional audio systems for cars, there are some systems which are capable of playing a plurality of compact discs selectively.
For example, in this type of audio system, the plurality of compact discs are stored in the predetermined magazine, and the magazine is integrated with the compact disc player which is placed in the trunk room.
Thus, regarding said audio system, the desired compact discs can be selected and played remotely operating the compact disc player by operating a switch key on the dashboard.
In regards to this type of car audio system, it is considered convenient if audio appliances, such as compact disc player, cassette tape recorder, and visual appliances, such as television receiver, can be turned on at will.
In such a case, if overall function of the audio system can be remotely controlled by using remote commander, e.g., a fellow passenger on the back seat can operate the audio system, it is considered very convenient.
However, if various audio and visual appliances are connected, the construction of remote commander becomes larger sized as well as number of operation keys are increased.
One of the methods to solve the above problem is that the pressing time of the operation key can be detected by detecting the running time of the remote control signals to be outputted from the remote commander and the motion can be shifted according to said pressing time.
Using this method, several shifting functions can be assigned to one operation key and the remote commander can be smaller sized accordingly.
However, this method has disadvantages. A disadvantage is that the remote control signal transmitted from the remote commander to the audio system may be interrupted by an obstruction positioned between the remote commander and the audio system. As such, reception of the remote control signal by the audio system is interrupted, resulting in erroneous operation of the audio system. By way of example, this may occur in a car having front and rear seat passengers, wherein a rear seat passenger utilizes the remote commander to transmit a desired remote control signal which is subsequently interrupted by the body of a front seat passenger. In addition, a further disadvantage is that since the actuation of many functions of the audio system is dependent upon the amount of time that an operation key is activated, the response time for activating these functions is undesirably increased.